1.3  Invoice

Where the Contractor and the Authority's Representative:

(a)  agree that the relevant damage constitutes Authority Damage, the Contractor shall be entitled to issue an invoice in respect of its reasonable and demonstrable costs incurred in reinstating the damage but only in respect of those costs that are the responsibility of the Authority under clause 1.1 (Damage); or

(b)  do not agree that the relevant damage constitutes Authority Damage, the matter shall be referred to the Dispute Resolution Procedure for resolution and if the dispute is resolved in the Contractor's favour, the Contractor shall be permitted to submit an invoice in respect of its reasonable and demonstrable costs incurred in reinstating the damage but only in respect of those costs that are the responsibility of the Authority under clause 1.1 (Damage).

(c)  agree an extension to the applicable Rectification Period in accordance with clause 1.2 (Discovery of Damage), such extended [Rectification Period] shall apply in respect of the relevant damage for the purposes of Schedule 4 (Payment Mechanism) to this Agreement;

(d)  do not agree either that there should be an extension to the relevant Rectification Period or what the extension should be, the matter shall be referred to the Dispute Resolution Procedure.